The owner where I play is a 1 pocket player and also a Diamond Dealer so he ordered several tables with extended sub rails taking pockets to 4 1/8” for 1 pocket.
It took a small adjustment but I actually like how they play and I play rotation on these tables as well. While the pocket is tighter, I came to the realization that when they extended the sub rails to take it to 4 1/8”, that this shortened the shelf a bit as compared to the other standard 4 1/2” Diamonds he has there. So I actually think that while the opening is smaller, the shelf being shortened actually lends to them playing a little better.
what's the name of the room?